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1.
Int J Mol Sci ; 22(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299003

RESUMO

Here, we designed paper sheets coated with chitosan, bacterial cellulose (nanofibers), and ZnO with boosted antibacterial and mechanical activity. We investigated the compositions, with ZnO exhibiting two different sizes/shapes: (1) rods and (2) irregular sphere-like particles. The proposed processing of bacterial cellulose resulted in the formation of nanofibers. Antimicrobial behavior was tested using E. coli ATCC® 25922™ following the ASTM E2149-13a standard. The mechanical properties of the paper sheets were measured by comparing tearing resistance, tensile strength, and bursting strength according to the ISO 5270 standard. The results showed an increased antibacterial response (assigned to the combination of chitosan and ZnO, independent of its shape and size) and boosted mechanical properties. Therefore, the proposed composition is an interesting multifunctional mixture for coatings in food packaging applications.


Assuntos
Biopolímeros/química , Biopolímeros/farmacologia , Celulose/química , Quitosana/química , Nanocompostos/química , Embalagem de Produtos/métodos , Óxido de Zinco/química , Anti-Infecciosos , Celulose/ultraestrutura , Escherichia coli , Testes Mecânicos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanocompostos/ultraestrutura , Nanofibras/química , Nanofibras/ultraestrutura , Propriedades de Superfície , Resistência à Tração , Difração de Raios X
2.
Int J Mol Sci ; 22(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200719

RESUMO

The potential of bacterial cellulose as a carrier for the transport of ibuprofen (a typical example of non-steroidal anti-inflammatory drugs) through the skin was investigated. Ibuprofen and its amino acid ester salts-loaded BC membranes were prepared through a simple methodology and characterized in terms of structure and morphology. Two salts of amino acid isopropyl esters were used in the research, namely L-valine isopropyl ester ibuprofenate ([ValOiPr][IBU]) and L-leucine isopropyl ester ibuprofenate ([LeuOiPr][IBU]). [LeuOiPr][IBU] is a new compound; therefore, it has been fully characterized and its identity confirmed. For all membranes obtained the surface morphology, tensile mechanical properties, active compound dissolution assays, and permeation and skin accumulation studies of API (active pharmaceutical ingredient) were determined. The obtained membranes were very homogeneous. In vitro diffusion studies with Franz cells were conducted using pig epidermal membranes, and showed that the incorporation of ibuprofen in BC membranes provided lower permeation rates to those obtained with amino acids ester salts of ibuprofen. This release profile together with the ease of application and the simple preparation and assembly of the drug-loaded membranes indicates the enormous potentialities of using BC membranes for transdermal application of ibuprofen in the form of amino acid ester salts.


Assuntos
Aminoácidos/química , Anti-Inflamatórios não Esteroides/farmacologia , Celulose/química , Ésteres/química , Ibuprofeno/farmacologia , Absorção Cutânea/efeitos dos fármacos , Pele/efeitos dos fármacos , Administração Cutânea , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Bactérias/metabolismo , Sistemas de Liberação de Medicamentos , Ibuprofeno/administração & dosagem , Ibuprofeno/química , Suínos
3.
Int J Mol Sci ; 22(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200927

RESUMO

Bacterial cellulose membranes (BCs) are becoming useful as a drug delivery system to the skin. However, there are very few reports on their application of plant substances to the skin. Komagataeibacter xylinus was used for the production of bacterial cellulose (BC). The BC containing 5% and 10% ethanolic extract of Epilobium angustifolium (FEE) (BC-5%FEE and BC-10%FEE, respectively) were prepared. Their mechanical, structural, and antioxidant properties, as well as phenolic acid content, were evaluated. The bioavailability of BC-FESs using mouse L929 fibroblasts as model cells was tested. Moreover, In Vitro penetration through the pigskin of the selected phenolic acids contained in FEE and their accumulation in the skin after topical application of BC-FEEs was examined. The BC-FEEs were characterized by antioxidant activity. The BC-5% FEE showed relatively low toxicity to healthy mouse fibroblasts. Gallic acid (GA), chlorogenic acid (ChA), 3,4-dihydroxybenzoic acid (3,4-DHB), 4-hydroxybenzoic acid (4-HB), 3-hydroxybenzoic acid (3-HB), and caffeic acid (CA) found in FEE were also identified in the membranes. After topical application of the membranes to the pigskin penetration of some phenolic acid and other antioxidants through the skin as well as their accumulation in the skin was observed. The bacterial cellulose membrane loaded by plant extract may be an interesting solution for topical antioxidant delivery to the skin.


Assuntos
Antioxidantes/administração & dosagem , Celulose/química , Epilobium/química , Fibroblastos/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Pele/efeitos dos fármacos , Administração Tópica , Animais , Bactérias/química , Fibroblastos/metabolismo , Camundongos , Pele/metabolismo , Suínos
4.
Int J Mol Sci ; 22(11)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071384

RESUMO

Since the effect of MFs (magnetic fields) on various biological systems has been studied, different results have been obtained from an insignificant effect of weak MFs on the disruption of the circadian clock system. On the other hand, magnetic fields, electromagnetic fields, or electric fields are used in medicine. The presented study was conducted to determine whether a low-frequency RMF (rotating magnetic field) with different field parameters could evoke the cellular response in vitro and is possible to modulate the cellular response. The cellular metabolic activity, ROS and Ca2+ concentration levels, wound healing assay, and gene expression analyses were conducted to evaluate the effect of RMF. It was shown that different values of magnetic induction (B) and frequency (f) of RMF evoke a different response of cells, e.g., increase in the general metabolic activity may be associated with the increasing of ROS levels. The lower intracellular Ca2+ concentration (for 50 Hz) evoked the inability of cells to wound closure. It can be stated that the subtle balance in the ROS level is crucial in the wound for the effective healing process, and it is possible to modulate the cellular response to the RMF in the context of an in vitro wound healing.


Assuntos
Cálcio/metabolismo , Campos Eletromagnéticos , Fibroblastos/metabolismo , Queratinócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Cicatrização/fisiologia , Animais , Linhagem Celular , Sobrevivência Celular/genética , Fibroblastos/citologia , Expressão Gênica , Humanos , Queratinócitos/citologia , Camundongos , Rotação , Cicatrização/genética , Proteína cdc42 de Ligação ao GTP/genética
5.
Microorganisms ; 8(11)2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33142809

RESUMO

The cultivation of bacteria sets a ground for studying biological processes in many scientific disciplines. The development of the bacterial population is commonly described with three factors that can be used to evaluate culture conditions. However, selecting only one of them for the optimization protocol is rather problematic and may lead to unintended errors. Therefore, we proposed a novel mathematical approach to obtain a single factor that could be used as the objective function to evaluate the whole growth dynamic and support the optimization of the biomass production process. The sigmoidal-shape curve, which is the commonly used function to plot the amount of biomass versus time, was the base for the mathematical analysis. The key process parameters, such as maximal specific growth rate and lag-phase duration were established with the use of mathematical coefficients of the model curve and combined to create the single growth parameter. Moreover, this parameter was used for the exemplary optimization of the cultivation conditions of Klebsiella pneumoniae that was cultured to be further used in the production of lytic bacteriophages. The proposed growth parameter was successfully validated and used to calculate the optimal process temperature of the selected bacterial strain. The obtained results indicated that the proposed mathematical approach could be effortlessly adapted for a precise evaluation of growth curves.

6.
Carbohydr Polym ; 161: 208-218, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28189230

RESUMO

The main aim of the current study was to evaluate the usefulness of the two-dimensional correlation analysis (2DCorr) technique in assessing the physicochemical properties of bacterial cellulose (BC) depending on the synthesis time and Komagataeibacter xylinus strain used for its production. It was demonstrated that 2DCorr analysis allows to characterize substantial changes in the structure of BC at the molecular level occurring during its synthesis, which are difficult to determine using ATR-FTIR spectral analysis. Furthermore, it was found that 2DCorr analysis allows to identify the differences in the structure and the properties of BC according to the bacterial strain used for its synthesis. It was concluded that 2DCorr analysis of the ATR-FTIR spectra may be a useful tool for controlling BC production in order to obtain material with the desired properties.


Assuntos
Celulose/química , Técnicas de Química Analítica/métodos , Gluconacetobacter xylinus/química , Técnicas de Química Analítica/normas
7.
Electromagn Biol Med ; 36(2): 192-201, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27786558

RESUMO

The current study describes properties of bacterial cellulose (BC) obtained from Komagataeibacter xylinus cultures exposed to the rotating magnetic field (RMF) of 50 Hz frequency and magnetic induction of 34 mT for controlled time during 6 days of cultivation. The experiments were carried out in the customized RMF exposure system adapted for biological studies. The obtained BC displayed an altered micro-structure, degree of porosity, and water-related parameters in comparison to the non-treated, control BC samples. The observed effects were correlated to the duration and the time of magnetic exposure during K. xylinus cultivation. The most preferred properties in terms of water-related properties were found for BC obtained in the setting, where RMF generator was switched off for the first 72 h of cultivation and switched on for the next 72 h. The described method of BC synthesis may be of special interest for the production of absorbent, antimicrobial-soaked dressings and carrier supports for the immobilization of microorganisms and proteins.


Assuntos
Acetobacteraceae/metabolismo , Celulose/biossíntese , Celulose/química , Campos Magnéticos , Rotação , Água/análise , Porosidade , Fatores de Tempo
8.
Carbohydr Polym ; 133: 52-60, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26344254

RESUMO

The aim of the study was to assess the influence of rotating magnetic field (RMF) on production rate and quality parameters of bacterial cellulose synthetized by Glucanacetobacter xylinus. Bacterial cultures were exposed to RMF (frequency f=50Hz, magnetic induction B=34mT) for 72h at 28°C. The study revealed that cellulose obtained under RMF influence displayed higher water absorption, lower density and less interassociated microfibrils comparing to unexposed control. The application of RMF significantly increased the amount of obtained wet cellulose pellicles but decreased the weight and thickness of dry cellulose. Summarizing, the exposure of cellulose-synthesizing G. xylinus to RMF alters cellulose biogenesis and may offer a new biotechnological tool to control this process. As RMF-modified cellulose displays better absorbing properties comparing to non-modified cellulose, our finding, if developed, may find application in the production of dressings for highly exudative wounds.


Assuntos
Celulose/biossíntese , Gluconacetobacter xylinus/metabolismo , Campos Magnéticos , Rotação , Glucose/metabolismo
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